OF THE FLl.CRA. 179 



trafolice^, internal, and are then generally simple, as 

 those of Polygonum, t. 1382, 756, &c. In a large 

 natural order, called Bubiacecs, these internal stipulas 

 in some cases embrace the stem in an undivided tube 

 above the insertion of the footstalks, like those of Po- 

 lygonum just mentioned : in others, as the Coftec, 

 Coffea arabica, and the Hamellia patens, Efigl. Bot. t. 

 2 ' , they are separate leaves between the footstalks, 

 but meeting just above their insertion. The Euro- 

 pean Rubiacece have whorled leaves, as Asperula Ga- 

 lium, Rubia, &c. ; but Asperula cynanchica, Engl. 

 Bot. t. 33, has sometimes two of its four leaves so 

 small as to look like stipulas, seeming to form an in- 

 termediate link between such as have whorled leat'es 

 and such as have opposite ones with stipulas. The 

 next step from Asperula is Diodia, and then Sperma- 

 cQce* In the two last the bases of the stipulas and 

 footstalks are united into a common tube. 



Some stipulas fall oif almost as soon as the leaves 

 are expanded, which is the case with the Tulip-tree, 

 Liriondendron tulipifera ; in general they last as long- 

 as the leaves. 



The absence or presence of these organs, though 

 generally an indication that plants belong to the same 

 natural order and even genus, is not invariably so. 

 Some species of Cistus have stipulas, others none, 

 which is nearly the same with grasses. The stipula 

 in this, one of the most distinct of all natural orders, 

 is peculiar, consisting of an internal white membrane 

 crowning the sheath of their leaf, and clasping the 

 culm. See Phalaris canariensis^ Engl, Bot. t. 13 10^ 



